In a second day of congressional testimony, Bernanke notes that the economic recovery has been slower than normal. But he says he doubts that the Great Recession permanently reduced the economy's growth potential.

Bernanke says he worries that more than 40 percent of America's unemployed ' 5.5 million people ' have been out of work for more than six months. He says that if the problem persists, more of the long-term unemployed will lose job skills and struggle to regain them.

Bernanke was speaking to the Senate Banking Committee on the second day of his semi-annual economic report to Congress.